Ignition timer for internal-combustion engines



oct. 23, 1923. 1,471,865

V. SHEARER IGNITION TIMER FOR INTERNAL COMBUSTION ENGINES Filed May 27 1921 Patented Oct. 23, 1923.

UNITED STATES 1.4.71sare PATENT OFFICE,

l VANGE SHEARER, on New YORK, N. Y.

IGNITION TIMERLFOR INTERNAL-COMBUSTION ENGINES.

Application led May 27, 1921.

Combustion Engines, of which the follow-v in is a specification.

il invention relates to timers such as emp oyed to control the ignition in multiple cylinder internal combustion engines, and while having other and more general fields of usefulness, is well adapted and designed for use in the ignition system of the well known Ford type of automobile.

In all devices of this character, so far as I am aware, their life is comparatively short, owing to the pitting or burning of the brass segments, and contact brush, or carbonizing of the coiidensite raceway of the timer, the current being continuously carried by the `movable contact or brush during its travel around the raceway.

The principal object of my present invention is to overcome this difficulty, and greatly lengthen the life of the timer, while increasing its efficiency, by the employment of means for making and breaking the electric circuit in such manner that the movable contact or brush does not receive the current until it reaches and is u on one end of a fixed contact, the circuit being broken as the brush reaches the opposite end of such fixed contact and before it passes 0H the same, the make and break of the electric ycurrent spark being controlled entirely by such means. The contact points are made of alloy capable of standing the high volta. e and amperage of electricity traveling t erethrough without pitting or burning the same. Another object is to provide means for equalizing the breaker contact at all times regardless of any end playthat may occur in the cam shaft. The details of construction and operation of my invention are hereinafter particularly set forth, in which other features of 'novelty and utility will be observed.

In the accompanying drawing:

Figure 1, is an inner end view of a timer constructed in accordance with my invention, the cam shaft, its support, and the movable contact brush being removed.

Fig. 2, is a sectional View taken on the broken lines 2-2 of Fig. l, the parts omitted in Fig. 1, being shown in place.

Serial No. 472,943.

Fig. 3, is a plan view of the movable contacts and their carrier.

Fig. 4,'is a sectional view taken on the broken line 4 4 of Fig. 3, and

Fig. 5, is a plan view of the Contact plate receiving the current from the magneto.

Similar reference characters denote like parts throughout the several views.

Referring to the drawing, the body 10, ef the timer is substantially hollow, and externally of a. shape similar to the present standard Ford timer, provided with the usual arm il, having an opening l2 at its free end to receive the connection for adjustment to advance or retard the spark. This body is of hard fiber or like insulating material and is molded or pressed to shape, and I prefer to strengthen the arm ll, and the opening therein by the insertion of a metallic core 13.

I also prefer to reinforce the bearingfor the cam shaft by molding therein a metallic tube 14. Both of these metallic reinforcements are insulated in the body l0.

The body 10, is interiorly rabbeted to forni an annular raceway l5, into which are seated quadrantally spaced fixed Contact plates 16, 17, 1S, 19. rThese fixed Contact plates are elongated segments of a circle and are pressed into place when molding the body member and in such manner that their outer surfaces are flush with the surface of the raceway.

Each of these plates is provided at the center of its outer edge with a right angle projection 20, which extends into the. body 10, below the surface of the raceway, there being an opening in each projection for the purpose hereafter described.

Spaced binding posts 21, 22, are mounted on the top of the body 10, and their terminals 23, 24, pass through openings in said body and enter the holes in the right angle projections of the two upper contact plates 16 and 17, making contact therewith.

The binding posts 25, and 2G, for connection with the two lower fixed Contact plates 18 and 19 are also mounted upon the top of the body 10, between the binding posts 21 and 22.

Conductor wires or strips 27 and 28, are connected at one end to the right angle projections on the lower contact plates 1S and 19, preferably by eyelets 29 and 30, inserted into the holes in said projections.

rIhese wires or strips 27 and 28 are emedded into the body 10, and pass from the contact plates 18 and 19, into contact With the terminals 31 and 32 ot the binding posts and it, such terminals passing through openiirjs in the i'iber body 10. have represented the upper ends ol' the conductors 27 and Q8, as passing into recesses in the lower ends et the terminals 31 and 32.

33, denotes a rotatable disk et insulating material ivithin the body 10, and provided on its inner side vfit-h an integral hub Si, through ivhich the cam shaft 35 passes, being` secured thereto by a pin 36, or other suitable means. rthe end ot the shaftt 35, is preterably threaded, upon which is screwed a lock nut 37.

This disk 33, also carries the movable con tact or brush 38. Upon the outer side ot the lisa there is a metallic plate 39, provided tvith a central opening surrounding the hub Si, and upon the inner side ot the disk there is another metallic plate L10, also provided vvith a central opening for the passage of the hub rhese tyyo metallic plates 89 and ett), are secured to the disk by screiys fit1 and 4Q, y-:hich pass through the disk.

rEhe plate stt), is ot less diameter than the disk. but has an integral projection L13, which extends to the periphery ot the disk at one point.

idjacent the end ot this projection 43, the plate i0 is provided ivith an opening i in register with this opening si. in the plte 10. there is an opening through the disk 33, ot someivhat greater diameter han the opening in said plate.

The brush 3S. projects through the opening si. in the plate d0, and is provided .vith annular flange 16. which takes against the edge oinA the plate surrounding the brush and thus holds it .vitiin the openings i4 and 5. Within the opening 45, in the disk and betvfeen the brush 3S, and back plate there is a spiral spring 47, which gives the brush a resilient bearing upon the surtace ot the racevvay 15, and fixed contacts 1G. 1T. 18. 19, ivhile at the same time the brush is securely retained in its carrier.

rFhe plate i0. is also provided with a pluralitj: ot uniformly spaced openings 4:8. of predetermined diameter and ivith their edges beveled inwardly as shown most clearly in Fig. in register ivith each ot' these openino's 8. there an opening 49, through the disk ot somewhat greater diameter than the openings 4S. in the plate 40, so that the beveled edges ot the openings 48. meet the top edges ot the openings 49. A ball contact 50. is inserted in each of the receptacles termed by the openings 119. back plate S9. and front plate 4:0, which balls are ot a size slightly smaller than the diameter of the openings 49. but of slightly7 larger diameter than the openings 4S, or so that While they may move Tithout undue friction Within the openings 49, they cannot project through the openings i8, except` to a predetermined degree. being held back by the beveled edges ot said openings. A spiral spring 51, is provided between each ot' these ball contacts 50, and the back plate 59. by which said balls are each normally held projecting to the desired extent through said openings stS, in lthe plate stt).

52, indicates a bracket, provided with a central longitudinal recess 5B, extending from one end to a predetermined distance from the other end ot the bracket.

This bracket is firmly secured to the inside ot the body member 10, by a screvior screivs 54, or in any other suitable manner. An elongated metallic plug 55. isv slidably fitted Within the recess 53, its torivard end being rounded. This plug .is provided ivith a stem 56, which projects through an opening in the closed end ot the bracket. upon rfhich projecting` end is secured a contact nut 57, there being a spiral spring surrounding the stem 5G, betiveen the plug 55, and the closed end ot the bracket 52, by means of which the 'forward and rounded end of the plug is normally held projecting a predetermined distance beyond the open end of the recess the nut 5T, limiting the outward movement ot the plug. A metallic plate 59, shaped to conform to the outer suriace oit the body 10, and which receives the electric currentI Ytrom the magneto (not shown), is secured to the body 10, l y a bolt Gt). and clamping nut G1.

Upon the inner end of the bolt Gt), there is screived a nut 62, proyided with con tact point G3. which makes and breaks the circuit through the timer as the contact nut 57, is brought into Contact therewith or draivn away from it by the spiral spring 5S. It will be apparent that by this con! struction the make and break is alloived to travel in the ad 'ance and retard position inthe timer shell.

During the revolution of the shaitt 35. carrying the disk the ball contacts 50, are successively brought into Contact with the plug contact 55, forcing its stem 56, inward and thereby bringing the contact nut 57, on its outer end into contact with the Contact point 68. on the end ot the bolt G0, thus closing the circuit to the moyablc contact or brush 38: this occurs at the exact time that the brush has reached and is upon one end of one ot the lixed contacts 16. 17, 18 or 19, and the operation is so timed that the brush reaches the opposite end of the Fixed contact just as the ball contact passes from Contact with the plug when the expansion of the spring 5S. separates the contacts 57 and G3. thus breaking the circuit, so that the brush 3S. is not charged with current while passing over the raceyvay between the respective fixed contacts, whereby the pitting or burning of the brass segments forming the fixed contacts or the carbonizing of the condensite raceway of the timer is prevented, also the pitting of the carbon contact brush, thereby greatly lengthening the usefulness of the timer.

The sprin bearings of the ball contacts and the maie and break contacts provide for any lost motion or end play of the cam shaft of the motor, equalizing the breaker contacts at all times.

I claim as my invention:

1. An ignition timer, comprising a casing of insulating material having an interior annular raceway, a plurality of contact plates fixed therein, a rotary shaft, a brush, a holder therefor secured to the shaft, a plurality of resilient contact members spaced apart in said holder, and make and break contacts co-acting therewith.

2. An ignition timer, comprising a hollow body of insulating material having an interior annular raceway, fixed contacts embedded therein, a rotary shaft, a brush and holder therefor connected with said shaft, a plurality of spaced ball contacts carried by the brush holder, and make and break contact coacting with said ball contacts by means of which the brush is intermittently charged with electric current.

3. An ignition timer, comprising a body of insulating material having an interior annular raceway, fixed contact plates embedded therein, a rotary shaft extending into the body perpendicularly to the raceway, a disk of insulating material connect-- ed to said shaft, a brush carried by said disk, a plurality of spaced ball contacts also carried by said disk, and make and break contacts whereby said brush is intermittently charged with electric current.

4. An ignition timer, comprising a body of insulating material having an interior annular raceway, spaced fixed contacts embedded therein, a rotary shaft extending into the body perpendicularly to the raceway, a disk of insulating material provided with a hub connected to said shaft, metallic plates, one upon each side of said disk and secured thereto by metallic members passing through the disk, said disk having an opening adjacent its periphery, there being an aligned opening in the plate on the inner side of said disk, a brush within the opening in the disk provided with an annular fiange, a spring within said opening and between the brush and the metallic plate on the outer side of the disk, a plurality of spaced ball contacts within openings in said disk and projecting through aligned openings in the metallic plate on the inner side of said disk, and make and break con` tacts within the body member which coact with said ball contacts to intermittently charge said brush with electric current.

5. In an ignition timer for internal com` bustion engines, and in combination, a hollow body having an interior annular race` way, a series of fixed contacts seated therein, binding posts with terminals engaging certain of said fixed contacts, intermediate binding posts, conductors engaging their terminals and extending therefrom through the insulating material of the body into contact with the remaining fixed contacts, a ro` tary shaft, a brush and holder therefor con` nected to said shaft, a plurality of spaced ball contacts carried by the brush holder, and make and break contacts coacting with said ball contacts whereby the brush is in` termittently charged with electric current.

Signed by me this 19th day of May, 1921.

VANCE SHEARER. 

